Graphite oxide

Graphene oxide is the oxidized form of graphene, a carbon allotype. Graphene oxide is made up of a single layer of oxidized carbon atoms. Scientists can chemically alter graphene oxide to produce graphene. They can also create it using chemical reactions. Although humans have been able to produce graphene oxide since the late 1800s, scientists did not recognize its potential until the early 2000s. Graphene oxide, like graphene, may play an important role in nanotechnology and have applications in industry, health, and technology.

Background

Carbon is one of the most abundant elements on the planet. It is essential for life as people know it. It is made up of six electrons, six protons, and six neutrons. Carbon’s elemental properties, which allow it to easily create covalent bonds, make it a unique substance. In the twenty-first century, scientists began exploring new possible applications of carbon in its different allotypes. Nanotechnology is based mostly on the use of carbon in various forms. Carbon nanotubes (CNTs), which are sheets of carbon that are only one atom thick and have been rolled into 3D structures, became an important advancement in the field of nanotechnology.

Scientists discovered methods of creating graphene in the early 2000s. Graphene is an allotrope of carbon, which means that it is one of the physical forms that elemental carbon can take. Graphene is a single layer of carbon atoms that are connected in a hexagonal, honeycomb structure. This structure makes it extremely strong. Although a scientist synthesized graphene oxide in the late 1800s, people did not begin producing it in large amounts until the early 2000s after scientists realized its characteristics, such as mechanical resistance and excellent conductivity, and possible applications.

Overview

Graphene oxide is a single-atom carbon layer that has oxygen-containing functional groups attached to both its sides. Graphene oxide is a two-dimensional material that can have a single-layer or multilayer construction. Layers of graphene oxide are separated by the functional oxygen groups that are bonded to the carbon.

Although scientists can use graphene oxide to create graphene, the two materials have numerous differences. Because of the oxygen present in the material, graphene oxide is not highly conductive. It also cannot absorb visible light as graphene can. Graphene oxide is more chemically reactive than graphene in part because of the oxygen in its structure. It is also soluble in water, unlike graphene.

To create graphene from graphene oxide, scientists can use chemical, thermal, or electrochemical processes. People most often use a chemical reaction to reduce graphene oxide to graphene because chemical reduction takes less time and is cheaper than the other methods. For example, thermal reduction can be expensive because it requires temperatures of more than 1000 degrees Celsius. However, thermal and chemical reactions create higher quality products than chemical reduction. The result of the reactions is called reduced graphene oxide (rGO).

Graphene oxide was first discovered in the late 1800s, though it was not considered an important material for the development of technology of medical applications until scientists made breakthroughs in the field of nanotechnology. This is a field of science that manipulates materials at a near-atomic level. Materials can exhibit unique qualities at the nanoscale. Carbon and its related materials have played important roles in the development of nanotechnology.

After scientists began exploring the use of graphene and graphene oxide in nanotechnology, scientists have developed the materials in larger quantities. People can synthesize graphene oxide through several methods. Graphene oxide is easier and less expensive to produce than graphene. One reason for this is that graphene oxide is soluble in water and other solvents.

Since the early 2000s, scientists have developed numerous possible applications for graphene oxide. They developed applications for graphene oxide in the nanomaterials and nanocoatings fields. The materials and coats created from graphene oxide are useful because they have unique properties not found in other, traditional coatings. Researchers have also found uses for graphene oxide because it is able to filter nanoparticles, organic materials, and salts. Desalination, the process of turning saltwater into freshwater, has been seen as an important technology to provide the world with freshwater in the future. In the 2010s, researchers developed a desalination system using graphene oxide.

Scientists also developed applications for the material in the medical field. Because graphene oxide, unlike graphene, is soluble in water, it has more possible applications in medicine than graphene. Scientists have used graphene oxide to sequence DNA. They also tested it in cancer and other medical treatments. Nanomaterials such as graphene can be useful in drug delivery inside the body because they can carry the drugs without changing them. Although researchers have widely explored the use of graphene oxide in medicine, they have also studied the material’s possible toxicity.

In the early 2020s, some unfounded claims about the use of graphene oxide in vaccines sparked an interest in the material. Governments and corporations around the world developed numerous vaccines to help combat the virus that caused the COVID-19 pandemic of the early 2020s. Misinformation about the vaccines, their side effects, and their ingredients spread quickly when the vaccines were first released and administered. One false claim made about the Pfizer/BioNTech COVID-19 vaccine was that it contained graphene oxide. The US Food and Drug Administration (FDA) and the companies that developed the vaccine released a list of ingredients, which did not include graphene oxide. Nevertheless, false information about the inclusion of graphene oxide in the vaccine was passed through social media and other media sources.

By 2024, scientists had conducted experiments to determine if graphite oxide could be used to combat environmental pollutants. They found it to be successful in removing contaminants from water. The element was able to remove highly hazardous contaminants that other technologies were unable to remove.

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